You know you've been there - staring at a lengthy email message for far too long, poring over every sentence and even word to make sure it is just right. That your content, structure, tone, and message are exactly what you had intended whether or not your intention was to inform, convince, persuade, attack, defend - whatever.
You just have convinced yourself it has to be just perfect before you hit send. 
Do it already!!!
But we forget when we are writing these paeans to perfection what we actually do as we are reading our own email messages. We literally scan through them in seconds, micro-seconds maybe. Who is it from matters most, who else is on copy is next in line of importance, followed by the subject line, and then and only then the content.
And by the content, the first 40 words or so mostly. After that, we either begin to space out mostly, or a few new messages, IMs, Tweets, and such have begun competing for our attention. Forty words, about twenty seconds of reading, tops.
So if you've been been staring at that one silly email for about an hour or more, or it has remained a 'work-in-progress' hiding in and out of your 'Drafts' folder all day long, just do yourself a favor and click 'send' already.
Chances are you are working yourself into a lather over something your recipients are going to consider for all of 20 seconds, as yours is likely one of about 200 messages they will see that day.
And if it is that important, that every word in the message needs to be just right, well then maybe you should pick up the phone and just call the person instead. You remember the phone, right? It is attached to that little device you carry around to get on the internet and send pictures to Facebook with.
But before you do that, you'd better practice your speech first. Do you have a mirror handy? Good.
Hello Billy Ray? This is Steve. I wanted to talk to you about...
Ugh. Maybe I'll just send that email after all...